Onboard control computers have become prevalent in motor vehicles. However, as safety, economy, and emissions requirements have continued to tighten, friction braking systems and traction control devices have not met the requirements set out in government regulations and the implicit demands of competitors' achievements. Successive generations of onboard control computers have acquired increasing data sensing and retention capability as the electronics have advanced.
Present external diagnostic and display apparatus, known as diagnostic tools, are commonly limited to reporting the data acquired by the onboard control computer itself. Increasingly, subtle subsystem failures in vehicles overload the ability of maintenance technicians, not simply to read the faults detected and stored by the diagnostic tools themselves, but to combine those readings with peripheral measurements and deduce corrective actions with both speed and accuracy.
Currently, in the automotive industry, there are both stand alone and hand-held diagnostic testers or tools used in connection with motor vehicle maintenance and repair. For example, hand-held diagnostic tools have been used to trouble-shoot faults associated with vehicular control units. Diagnostic tools detect faults based on Diagnostic Trouble Codes or DTCs that are set in the vehicle's onboard control computer. A DTC can be triggered and stored when there is a problem with the vehicle. A technician then retrieves the DTC using a diagnostic tool, repairs the associated problem and then deletes the DTC from the vehicle's computer.
Problems in the diagnostic tool, such as failure of hardware, software, and connection with the vehicle, are difficult to correct. The current diagnostic tools will only show a message indicating there is a communication failure or other error. Then, the technical service personnel have to be called and the technical service personnel have to ask several questions in an attempt to determine whether the user had the diagnostic tool properly configured or not. The questions asked and answered will take an inordinate amount of time. In addition, the entry of the answers may or may not be correct. The verbal relay of the information from the user of the diagnostic tool to the technician has an inherent flaw of potential inaccuracies and a delay of time.
Accordingly, it is desirable to provide a method and apparatus that will allow a user to diagnose the configuration of the diagnostic tool in a more cost effective and efficient manner.